Well, they allow us access to the vast amount of writing written in them, which covers topics from religion to culture to daily life to spoken language to history over a span of thousands of years. (From 3300 BC to 400 AD to be more specific). read more
EDIT: also, a lot of people think that hieroglyphics were only used in the tombs of pharaohs, but this isn’t true, we have for example large numbers of letters written by common people in a variation of hieroglyphics. read more
Before: Hieroglyphics just told the story of the pharaoh's life in his tomb. Now: Hieroglyphics were used to decorate the pharaoh's tomb and helped him get to the afterlife. Top Ten Reasons Why You Want to Know How to Write Hieroglyphics 10. Because it looks cool 9. It was an important part of tomb decoration 8. Important people knew how to write it 7. read more
Hieroglyphics significance is to tell us about ancient Egypt and the Rosetta stone. Look up Jean Francois Champollion because he decrypted Hieroglyphics. read more